Short definition
ABS cement is the black solvent cement used to join ABS DWV pipe and fittings. It contains MEK (methyl ethyl ketone) plus dissolved ABS resin — softens the surfaces, then evaporates to leave a chemical weld. It is not interchangeable with PVC cement, despite looking similar on the shelf.
What it is
ABS cement is a one-step product. Unlike PVC, it does not require a separate primer — the cement itself softens the pipe wall enough to bond. Apply to both surfaces, assemble within the working time (1 to 2 minutes at 70°F), and hold the joint in alignment for at least 30 seconds while the bond sets.
There are three product types on the shelf, and only the right one is code-legal for the joint:
- ABS cement (black). For ABS-to-ABS joints.
- PVC primer (purple) plus PVC cement (clear, blue, or amber). For PVC-to-PVC.
- ABS-to-PVC transition cement (green). For the rare transition joint where ABS meets PVC.
“All-purpose” or “universal” solvent cement exists, but local codes often require listed material-specific cements on inspected work. Don’t use universal on permitted DWV.
Why it matters to a homeowner
ABS cement is the right product for repairing ABS DWV in 1970s and ’80s Seattle homes. Reaching for PVC cement on an ABS pipe makes a joint that won’t bond and fails on first water flow. The colors exist as a visual code-inspection signal — black means ABS, purple means PVC primer, green means transition. An inspector glancing at your work reads the colors before reading the labels.
When you’ll encounter this term
- A repair on a 1970s–80s ABS DWV branch.
- A connection between an old ABS branch and a new PVC stack during a remodel.
- A code inspection on permitted DWV work.
Common variants and not the same as
- ABS cement vs. PVC cement. Different chemistries, won’t cross-bond.
- ABS-to-PVC transition cement. A separate product specifically formulated for the rare ABS-to-PVC joint.
- All-purpose solvent cement. Works mechanically, but may fail local code inspection.
Common failure modes
- Wrong cement on the pipe. Won’t bond. Joint fails immediately.
- Skipped deburr. Burr defeats the contact area.
- Old, thickened cement. Solvent has evaporated through a poor lid seal. Toss.
- Joint released too early. Pipe pushes back as cement softens, leaving a weak seam. Hold 30 seconds.
Washington note
Washington’s adopted UPC (with state amendments) accepts ABS for DWV, but the regional supply chain leans heavily PVC. ABS DWV is more common in 1970s–80s Seattle stock and along the BC border. Mixed ABS-to-PVC joints have a checkered code-acceptance history: some jurisdictions accept the transition cement; some require a no-hub mechanical coupling instead. Verify with the local AHJ — Seattle SDCI, Tacoma Permits, your county building department — before buying transition cement for permitted work. The mechanical coupling is the more inspector-friendly option and saves a callback if the inspector disagrees with your cement choice.